Hydrogen-Rich Water Intake Accelerates Oral Palatal Wound Healing via Activation of the Nrf2/Antioxidant Defense Pathways in a Rat Model

The wound healing process attempts to restore the integrity and function of the injured tissue. Additionally, proinflammatory cytokines, growth factors, and oxidative stress play important roles in wound healing. The aim of this study was to determine whether hydrogen-rich water intake induces the activation of the Nrf2/antioxidant defense pathway in rat palatal tissue, thereby reducing systemic oxidative stress and proinflammatory cytokine levels and promoting healing-associated genes. A circular excisional wound was created in the oral palatal region, and the wound healing process was observed. The rats were divided into two experimental groups in which either hydrogen-rich water or distilled water was consumed. In the drinking hydrogen-rich water, the palatal wound healing process was accelerated compared to that in the control group. As molecular hydrogen upregulated the Nrf2 pathway, systemic oxidative stresses were decreased by the activation of antioxidant activity. Furthermore, hydrogen-rich water intake reduced proinflammatory cytokine levels and promoted the expression of healing-associated factors in rat palatal tissue. In conclusion, hydrogen-rich water intake exhibited multiple beneficial effects through activation of the Nrf2/antioxidant defense pathway. The results of this study support the hypothesis that oral administration of hydrogen-rich water benefits the wound healing process by decreasing oxidative stress and inflammatory responses

Hydrogen-Rich Water Intake Accelerates Oral Palatal Wound Healing via Activation of the Nrf2/Antioxidant Defense Pathways in a Rat Model

The wound healing process attempts to restore the integrity and function of the injured tissue. Additionally, proinflammatory cytokines, growth factors, and oxidative stress play important roles in wound healing. The aim of this study was to determine whether hydrogen-rich water intake induces the activation of the Nrf2/antioxidant defense pathway in rat palatal tissue, thereby reducing systemic oxidative stress and proinflammatory cytokine levels and promoting healing-associated genes. A circular excisional wound was created in the oral palatal region, and the wound healing process was observed.The rats were divided into two experimental groups in which either hydrogen-rich water or distilled water was consumed. In the drinking hydrogen-rich water, the palatal wound healing process was accelerated compared to that in the control group. As molecular hydrogen upregulated the Nrf2 pathway, systemic oxidative stresses were decreased by the activation of antioxidant activity. Furthermore, hydrogen-rich water intake reduced proinflammatory cytokine levels and promoted the expression of healing-associated factors in rat palatal tissue. In conclusion, hydrogen-rich water intake exhibited multiple beneficial effects through activation of the Nrf2/antioxidant defense pathway.The results of this study support the hypothesis that oral administration of hydrogen-rich water benefits the wound healing process by decreasing oxidative stress and inflammatory responses

ヒト歯肉線維芽細胞における酸化ストレスに対するレスベラトロール，ケルセチン，及びN-アセチルシステインの生物学的影響

In periodontitis, production of reactive oxygen species (ROS) by neutrophils induces oxidative stress and deteriorates surrounding tissues. Antioxidants reduce damage caused by ROS and are used to treat diseases involving oxidative stress. This study summarizes the different effects of resveratrol, quercetin, and N-acetylcysteine (NAC) on human gingival fibroblasts (HGFs) under oxidative stress induced by hydrogen peroxide. Real-time cytotoxicity analyses reveals that resveratrol and quercetin enhanced cell proliferation even under oxidative stress. Of the antioxidants tested, resveratrol is the most effective at inhibiting ROS production. HGFs incubated with resveratrol and quercetin up-regulate the transcription of type I collagen gene after 3 h, but only resveratrol sustained this up-regulation for 24 h. A measurement of the oxygen consumption rate (OCR, mitochondrial respiration) shows that resveratrol generates the highest maximal respiratory capacity, followed by quercetin and NAC. Simultaneous measurement of OCR and the extracellular acidification rate (non-mitochondrial respiration) reveals that resveratrol and quercetin induce an increase in mitochondrial respiration when compared with untreated cells. NAC treatment consumes less oxygen and enhances more non-mitochondrial respiration. In conclusion, resveratrol is the most effective antioxidant in terms of real-time cytotoxicity analysis, reduction of ROS production, and enhancement of type I collagen synthesis and mitochondrial respiration in HGFs

Influence of Bacterial Endotoxin on Mucosal Immune Response to Phosphorylcholine

Bacterial lipopolysaccharide (LPS), a component of the outer membrane of gram-negative bacteriathat initiates inflammation by activation innate immune responses through Toll-like receptor 4(TLR4). However, the influence of LPS on the mucosal immune reactions remains to be addressed.This study was examined the effect of LPS in nasal vaccination model. BALB/c and C57BL/6 micewere nasally immunized with keyhole limpet hemocyanin (KLH) conjugated with hapten phosphorylcholine (PC) or trinitrophenol (TNP) with LPS as a mucosal adjuvant, in the presence orabsence of cholera toxin (CT). The antibody titers were measured in serum, saliva, and nasal washfluids by an enzyme-linked immunosorbent assay (ELISA) in IgM, IgG, and IgA isotype-specificmanner. The epitope-specific antibody production induced in blood and mucosal fluid was furtherenhanced by LPS for all isotypes examined. Besides, LPS, which has rarely been regarded as a mucosal adjuvant, was tested for its adjuvanticity by comparing the nasal immunization with PC-KLH plus LPS or with PC-KLH plus CT. LPS showed high adjuvanticity almost equal to CT. Possible differences of LPS from CT as a mucosal adjuvant remains to be elucidated